The Federal Environment Minister Tony Burke says he was forced to approve three mining and gas projects earlier than he would have liked because the New South Wales Government leaked commercially sensitive information.

Mr Burke has given the green light to the Maules Creek mine and the nearby Boggabri extension in the Leard Forest, as well as the Gloucester CSG development, all in northern New South Wales.

He says the approvals are subject to further strict conditions that will be negotiated directly between his office and the company.

Mr Burke says the New South Wales Government will remain in the dark on their progress because of the leaking of a letter he wrote to Resources Minister, Chris Hartcher, before Christmas.

"New South Wales will have no notice, no access, no consultation with any of the decisions I make for these three projects," he said.

"Quite simply the NSW Government decided to strategically leak parts of where we were up to with bits of it being reported, not all of it being reported.

"Effectively we had a situation where market-sensitive information was starting to drip feed into the market.

"It's a pretty irresponsible pathway to choose and something that no state government has ever done before."

Yesterday's announcement came after the minister said last Thursday that he would defer a decision on the massive Maules Creek mine for up to three months.

Whitehaven Coal's open-cut mine will form a mega-mine complex, clearing around 5,000 hectares of the Leard State Forest, to produce 23 million tonnes of coal annually.

Tony Burke says if the conditions are not met the projects will not go ahead.

"It's the first time in any approval I have put forward an approval with so many conditions yet to be resolved and where, at the time of the approval, it is entirely unclear whether or not the project will be able to go ahead," he said.

"They have to do more work, come back to my satisfaction before we know whether or not the project will actually go ahead."

Chris Hartcher says Mr Burke has been caught out playing political games and undermining investment confidence.

Mr Hartcher says he welcomes the approvals, albeit delayed, and says the State Government supports the scientific process underpinning resource project approvals.

Community anger

Environmental groups have reacted angrily to the approval of the mines, despite the conditions including the establishment of a permanent biodiversity corridor.

NSW Greens MLC Cate Faehrmann says she is appalled.

"I don't know how any environment minister in their right mind can approve the Maules Creek and Boggabri proposal and say that he's looking after the environment," she said.

Boggabri farmer and anti-project campaigner Phil Laird says the minister has merely caved in politically and sold out the environment.

"We've provided him with quite a lot of scientific evidence, which we thought would take around about three months for him to grind through and to form a proper view.

"It seems to us he's simply crumbled under the pressure from the State Government and it's very questionable to us about whether he's a proper person to administer the EPBC Act."

Carmel Flint, from the Northern Inland Council for the Environment says a legal challenge is looming.

"Certainly there are strong provisions in those laws that a mine should not be approved on the basis of false and misleading information," she said.

"So we believe there may be some avenues to pursue there."

Federal Independent MP, Rob Oakeshott, says both major parties have underestimated the level of community opposition to coal seam gas developments.

The Gloucester CSG project is in Mr Oakeshott's electorate and he says he is gutted by the decision.

"Both major parties are misreading what's happening in communities when farmers groups, the CWA, environmental groups, and people who've never protested or showed any want to do civil disobedience whatsoever are now starting to actively consider it," he said.

"If the major parties can't see this in communities right now, and the level of frustration through the roof, then they really are busted and have forgotten where their roots really are."

The Minerals Council says the projects will help underpin the long-term economic strength of the New England north-west region.

The ABC contacted Whitehaven Coal and the Maules Creek Community Council for a response.

Neither wished to give an interview until after reading Tony Burke's conditions of approval more closely.